feat(users/Profpatsch): add read-http

reads a http request or response from stdin, and parses its headers
into a netencoded record.

Darn rust code took way too long to write.

Change-Id: Ie99faa6d4bbd4996fa4e43fb119a11d85b611c99
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2447
Reviewed-by: Profpatsch <mail@profpatsch.de>
Tested-by: BuildkiteCI

users/Profpatsch/read-http/default.nix

@@ -0,0 +1,19 @@
+{ depot, pkgs, ... }:
+
+let
+
+  # reads a http request (stdin), and writes all headers to stdout, as netencoded dict
+  read-http = depot.users.Profpatsch.writers.rustSimple {
+    name = "read-http";
+    dependencies = [
+      depot.users.Profpatsch.rust-crates.httparse
+      depot.users.Profpatsch.netencode.netencode-rs
+      depot.users.Profpatsch.arglib.netencode.rust
+    ];
+  } (builtins.readFile ./read-http.rs);
+
+in {
+  inherit
+    read-http
+    ;
+}